Note: Unless you are using a severely outdated operating system or CPU, you most likely want to always download the x64 (64-bit) version of Ultimate Doom Builder.
The 64-bit version has less limitations on the total size of the project that you can load and edit, while the x86 (32-bit) version of Ultimate Doom Builder only exists for compatibility with older PCs.
If not sure, follow these instructions to find out whether your system is 64-bit: Which version of Windows operating system am I running?
The 64-bit version has less limitations on the total size of the project that you can load and edit, while the x86 (32-bit) version of Ultimate Doom Builder only exists for compatibility with older PCs.
If not sure, follow these instructions to find out whether your system is 64-bit: Which version of Windows operating system am I running?
All recent versions
Ultimate Doom Builder R4282
02 Jan 2026
Really fixed a problem where a redraw could be triggered when a texture was loaded even though accessing the map was not safe now (initial non-working fix in 754aa4a)
Ultimate Doom Builder R4279
01 Jan 2026
Applied several code style recommendations to source files
Ultimate Doom Builder R4276
01 Jan 2026
Toolbar buttons now show their function and hotkey in their tool tips as expected on Linux/Mono
Ultimate Doom Builder R4275
01 Jan 2026
Improved visibility of toolbar buttons and menu entries on Linux/Mono
Improved visibility of buttons in the jitter forms on Linux/Mono
Improved visibility of buttons in the jitter forms on Linux/Mono
Ultimate Doom Builder R4274
31 Dec 2025
Files from malformed ZIP files that use a backslash instead of a forward slash as directory separator can now be loaded. Fixes #1281